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TableGenerator (Java EE 5 SDK) - Java Platform, Enterprise Edition v5.0 API Specifications

Java EE 5 SDK

javax.persistence
Annotation Type TableGenerator


@Target(value={TYPE,METHOD,FIELD})
@Retention(value=RUNTIME)
public @interface TableGenerator

This annotation defines a primary key generator that may be referenced by name when a generator element is specified for the GeneratedValue annotation. A table generator may be specified on the entity class or on the primary key field or property. The scope of the generator name is global to the persistence unit (across all generator types).

    Example 1:
    
    @Entity public class Employee {
        ...
        @TableGenerator(
            name="empGen", 
            table="ID_GEN", 
            pkColumnName="GEN_KEY", 
            valueColumnName="GEN_VALUE", 
            pkColumnValue="EMP_ID", 
            allocationSize=1)
        @Id
        @GeneratedValue(strategy=TABLE, generator="empGen")
        public int id;
        ...
    }
    
    Example 2:
    
    @Entity public class Address {
        ...
        @TableGenerator(
            name="addressGen", 
            table="ID_GEN", 
            pkColumnName="GEN_KEY", 
            valueColumnName="GEN_VALUE", 
            pkColumnValue="ADDR_ID")
        @Id
        @GeneratedValue(strategy=TABLE, generator="addressGen")
        public int id;
        ...
    }
 

Since:
Java Persistence 1.0

Required Element Summary
 String name
          (Required) A unique generator name that can be referenced by one or more classes to be the generator for id values.
 
Optional Element Summary
 int allocationSize
          (Optional) The amount to increment by when allocating id numbers from the generator.
 String catalog
          (Optional) The catalog of the table.
 int initialValue
          (Optional) The initial value to be used when allocating id numbers from the generator.
 String pkColumnName
          (Optional) Name of the primary key column in the table.
 String pkColumnValue
          (Optional) The primary key value in the generator table that distinguishes this set of generated values from others that may be stored in the table.
 String schema
          (Optional) The schema of the table.
 String table
          (Optional) Name of table that stores the generated id values.
 UniqueConstraint[] uniqueConstraints
          (Optional) Unique constraints that are to be placed on the table.
 String valueColumnName
          (Optional) Name of the column that stores the last value generated.
 

Element Detail

name

public abstract String name
(Required) A unique generator name that can be referenced by one or more classes to be the generator for id values.

table

public abstract String table
(Optional) Name of table that stores the generated id values.

Defaults to a name chosen by persistence provider.

Default:
""

catalog

public abstract String catalog
(Optional) The catalog of the table.

Defaults to the default catalog.

Default:
""

schema

public abstract String schema
(Optional) The schema of the table.

Defaults to the default schema for user.

Default:
""

pkColumnName

public abstract String pkColumnName
(Optional) Name of the primary key column in the table.

Defaults to a provider-chosen name.

Default:
""

valueColumnName

public abstract String valueColumnName
(Optional) Name of the column that stores the last value generated.

Defaults to a provider-chosen name.

Default:
""

pkColumnValue

public abstract String pkColumnValue
(Optional) The primary key value in the generator table that distinguishes this set of generated values from others that may be stored in the table.

Defaults to a provider-chosen value to store in the primary key column of the generator table

Default:
""

initialValue

public abstract int initialValue
(Optional) The initial value to be used when allocating id numbers from the generator.

Default:
0

allocationSize

public abstract int allocationSize
(Optional) The amount to increment by when allocating id numbers from the generator.

Default:
50

uniqueConstraints

public abstract UniqueConstraint[] uniqueConstraints
(Optional) Unique constraints that are to be placed on the table. These are only used if table generation is in effect. These constraints apply in addition to primary key constraints.

Defaults to no additional constraints.

Default:
{}

Java EE 5 SDK

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